입자를 포함한 미세유체플랫폼기술의 개발 및 응용

Abstract

For a past few decades, microfluidic-based lab-on-a-chip (LOC) platforms have been extensively developed for their numerous advantages (e.g., cost effectiveness, high throughput, and high sensitivity). They allow a variety of analyses to be carried out effectively compared to conventional laboratory-based methods. Furthermore, incorporation of microparticles (e.g., microbeads or hydrogels) into the microfluidic platforms creates strong synergistic effects since the microparticle itself provides multiple benefits: three-dimensional particles can act as a mobile substrate (transportation, mixing, or sorting of targets); their surface can be functionalized (widely applicable, depending on target applications); they offer a huge analytical surface (rapid and sensitive analysis); and they allow multiplex analysis (high throughput) using encoding/decoding. Recent advancements in particle-engineering technologies (e.g., evolutions in shape, size, multi-compartmentalization, etc.) have accelerated the potential of particle-incorporated microfluidic platforms. Several unit microfluidic particle manipulation functions (e.g., transport, sort, trap, release, etc.) need to be properly combined to carry out specific tasks. Thus, there has been considerable research into particle-manipulation strategies in microfluidic devices. Typically, particle-manipulation methods can be classified into two approaches: (i) passive and (ii) active. Passive approaches use the geometries of microchannel networks; these are simple but lack functionality. Active approaches use external stimuli; although these can achieve high functionality, the overall system can be complicated. To address the limitations of those conventional approaches, this dissertation describes a novel particle manipulation method that uses deformation characteristics. This approach provides high-functionality with simple device configurations. Deformability of soft particles (e.g., droplets, hydrogels) and soft structures (e.g., elastic PDMS (polydimethylsiloxane) structures) are exploited to effectively manipulate different types of particles in microfluidic devices. The dissertation discusses the design, concept, characterization, and practical applications of the developed devices and methods. Chapter 1 presents the background, motivation for, and objective of the dissertation. Chapter 2 discusses an on-demand droplet merging method based on droplet deformability. Chapters 3 and 4 discuss structure deformation–based particle manipulation methods. Chapter 5 summarizes the dissertation and presents insights into the future outlook.